[Amps] Alpha 87A No Output

[Frank Kirschner]

All of a sudden, my Alpha 87A has stopped amplifying. It had sat for about
a month with no use. Everything seems normal: the correct lights come on,
the amp seems to switch into operate mode, but the output power is equal to
the input power. When I transmit, the serial port puts out a series of
RM50E00, RM50D00, ending with RM00000. I don't know what else to look at.

Any suggestions before I start taking it apart?

Thanks.

73,
Frank
KF6E